1. Field of the Invention
The invention relates generally to electronic equipment having a housing that can receive a stylus as pointing device and, more particularly, the invention relates to a stylus retaining and releasing mechanism for such a stylus-receiving housing.
2. Description of the Related Art
Information appliances presently constitute an important market for electronic industries. “Information appliances” broadly designate electronic products that can communicate via, for example, internet network. Information appliances should be therefore able to connect to internet, allow telephonic communication, receive and send out data, etc., while further being easily transportable. Information appliances that are presently commercialized include various types of devices such as mobile phones, Personal Digital Assistants (PDA), Web PAD.
Among those various types of devices, PDA devices are a representative example of information appliance development trend. PDA devices are hand-held electronic devices that can typically accomplish telecommunication operations of conventional mobile phone and multi-task operations of electronic organizer.
FIG. 1 is a perspective view that shows a conventional PDA device. From an external aspect, a conventional PDA device 100 typically comprises a housing 200 and a display screen 400. For convenience consideration, the PDA device 100 further may be provided with a separate stylus 300 as pointing device, in which case the display screen 400 is a touch panel display screen.
To conveniently dispose the stylus 300, the housing 200 of the PAD device 100 is conventionally provided with a cavity 210 therein to receive the stylus 300. The arrangement of the stylus 300 in the housing 200 should ensure a hold of the stylus 300 in the housing 200 and, meanwhile, allow a user to easily extract the stylus 300 from the housing 200.
Various mechanisms are conventionally used to hold and immobilize the stylus 300 once it is inserted in the cavity 210. One mechanism consists of, for example, adjusting the size of the cavity 210 and the size of the stylus 300 so that a tight contact there between, occurring when the stylus 300 is inserted in the cavity 210, ensures the hold of the stylus 300. To ensure a tight hold, an additional resilient element (not shown) may be conventionally added in the cavity 210 to press on the stylus 300. The above methods have the inconvenience of damaging the external surface of the stylus 300.
Another method consists of arranging a resilient retaining device (not shown) in the housing 200. When the stylus 300 is slidably inserted in the cavity 210, the resilient retaining device can resiliently insert in a retaining slot 310 formed on the stylus 300 to hold and immobilize the stylus 300 in the cavity 210. The resilience of the resilient retaining device is such that its hold can be easily overcome when the user pulls out the stylus 300. However, with the stylus 300 substantially enclosed in the cavity 210 while only a slight portion thereof protrudes out of the housing 200, it may be difficult for the user to grasp and extract the stylus 300.
To cure the above deficiency, some housing may be provided with an additional spring in the cavity and a latch mounted proximate to the external opening of the cavity 210 (not shown). When the cavity 210 receives the stylus 300 therein, the stylus 300 further presses on the spring in the cavity 210 (not shown) while the latch engages in a slot 312 on a portion of the stylus 300 that protrudes over the cavity 210. The latch is directed to immobilize and hold the stylus 300 against the resilient force that is exerted by the spring on the stylus 300 when the stylus 300 is arranged in the cavity 210. When the stylus 300 is to be extracted, the user disengages the latch and, under the resilient force of the spring, the stylus 300 is ejected out of the cavity 210.
The above mechanism may render the extraction of the stylus easier, but it necessitates an important amount of elements, and from user-convenience consideration, its operation still may not be satisfactory.